On Mon, 11 Jan 2021 05:28:55 +0100, Davidlohr Bueso wrote: > > Currently a tasklet is used to transmit input substream buffer > data. However, tasklets have long been deprecated as being too > heavy on the system by running in irq context - and this is not > a performance critical path. If a higher priority process wants > to run, it must wait for the tasklet to finish before doing so. > > Deferring work to a workqueue and executing in process context > should be fine considering the callback already does > f_midi_do_transmit() under the transmit_lock and thus changes in > semantics are ok regarding concurrency - tasklets being serialized > against itself. > > Cc: Takashi Iwai <ti...@suse.de> > Signed-off-by: Davidlohr Bueso <dbu...@suse.de>
The patch looks good to me. Reviewed-by: Takashi Iwai <ti...@suse.de> BTW, now I found that the driver doesn't have the cancel call for tasklet or work at the unbind. Practically seen it's no big problem, but its lack is a bait for syzbot. We may need to just call cancel_work_sync() somewhere, probably at f_midi_drop_out_substreams() or f_midi_disable(), but it can be in another patch. thanks, Takashi